JP2006165305A - Treatment device, treatment liquid supply method and treatment liquid supply program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve treatment quality by improving reproducibility of the treatment liquid discharge pressure (especially, the pressure in discharge starting time) from a nozzle. <P>SOLUTION: The resist liquid supply mechanism 132 fills in advance a pump 150 with a resist liquid R for at least one application treatment via a suction tube 148 from a bottle 146 storing the resist liquid R, the resist liquid is forcibly fed to a resist nozzle 120 from the pump 150 at a prescribed pressure via a discharge tube 136 in application treatment, and the resist liquid R is discharged at a prescribed flow rate on a substrate G from the resist nozzle 120. A controller 160 controls each of opening/closing valves 152, 158, 162 of the resist liquid supply mechanism 132, the pump 150, and the nozzle movement mechanism 134 in accordance with programmed sequence and various set values. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a processing apparatus, a processing liquid supply method, and a processing liquid supply program for supplying a predetermined processing liquid from a nozzle to a substrate to be processed and performing a desired processing.

  Conventionally, in a photolithography process in a manufacturing process of a flat panel display (FPD) such as an LCD, a resist solution is formed on a substrate to be processed (such as a glass substrate) using a long resist nozzle having a slit-like discharge port. 2. Description of the Related Art A coating apparatus that applies a spinless coating is often used.

In such a spinless coating apparatus, as disclosed in, for example, Patent Document 1, a substrate is horizontally placed on a mounting table or a stage, and the substrate on the stage and a discharge port of a long resist nozzle are disposed. A small gap of about 100 μm is set between and the resist nozzle is moved in the scanning direction (generally in the horizontal direction perpendicular to the longitudinal direction of the nozzle) above the substrate, and the resist solution is discharged onto the substrate in a band shape and applied. . By simply moving the long resist nozzle once from one end of the substrate to the other end, the resist coating film can be formed with a desired film thickness without dropping the resist solution outside the substrate.
JP-A-10-156255

  The required performance emphasized in the spinless type coating apparatus as described above is the uniformity of the resist film thickness, particularly the reproducibility immediately after the start of coating. In the coating process, the reproducibility of the scanning speed can be ensured with sufficiently high accuracy, but the reproducibility of the discharge operation is a problem.

  Normally, in this type of coating apparatus, a piston pump is used as a pump for the resist supply unit, and the piston is reciprocated with a fixed stroke corresponding to the amount of resist solution discharged in one time, that is, for one substrate. I try to let them. That is, prior to the coating process, the piston is moved back by a set stroke, and a set amount of resist solution is sucked or filled into the pump from the resist supply source. Then, when the coating process is started, the piston is moved forward at a predetermined speed by the same stroke as that during the backward movement in conjunction with the nozzle scanning, and the set amount (the amount previously sucked in) ) Is sent to the nozzle at a predetermined pressure, and the resist liquid is discharged from the nozzle onto the substrate at a predetermined flow rate.

  However, the pump pressure at the start of coating varies, making it difficult to control film thickness with high reproducibility. In particular, at the start of application, the pump internal pressure may be too high and the resist solution may drop from the nozzles. Conversely, the pump internal pressure may be too low and air bubbles may be mixed into the resist solution from the nozzle discharge port. Further, the error in the internal pressure of the pump at the start of coating may affect the pump discharge pressure during coating, and the film thickness of the entire coating film may not be as set.

  The present invention has been made in view of the problems of the prior art, and improves the processing quality by improving the reproducibility of the pressure at which the processing liquid is discharged from the nozzle (particularly the pressure at the start of discharge), It is an object to provide a processing liquid supply method and a processing liquid supply program.

  In order to achieve the above object, a processing apparatus of the present invention includes a nozzle that discharges a predetermined processing liquid to a substrate to be processed, a storage unit that stores the processing liquid, and a storage unit that stores the processing liquid. A pump for sucking the processing liquid through one pipe and pumping the processing liquid through the second pipe toward the nozzle; a first valve provided in the first pipe; A second valve provided in the second pipe, and the pump and the second valve in a state where the second valve is closed after the pump has sucked the processing liquid from the reservoir. A standby pressure control unit that controls the pump by a pressure feedback method so that the pressure of the processing liquid remaining in the flow path between the two and the reference liquid matches a preset reference standby pressure.

  In the processing liquid supply method of the present invention, the processing liquid stored in the storage section is filled into the pump via the first pipe provided with the first valve, and the second valve is provided from this pump. A processing liquid supply method for pumping a processing liquid to a nozzle through a second pipe, discharging the processing liquid from the nozzle and supplying the processing liquid to a substrate to be processed, and opening the first valve A first step of closing the second valve, causing the pump to perform a suction operation for a predetermined stroke, and filling the pump with a treatment liquid from the reservoir by an amount corresponding to the stroke, and a second valve While maintaining the closed state, the first valve is switched from the open state to the closed state so that the pressure of the processing liquid remaining in the flow path between the pump and the second valve matches the desired reference standby pressure. A second step of controlling the pump in a pressure feedback manner, and a first valve The second valve is switched from the closed state to the open state while maintaining the state, and the pump performs the discharge operation for a predetermined stroke, and the processing liquid is discharged from the nozzle toward the substrate in the amount corresponding to the stroke. 3 steps.

  Further, the processing liquid supply program of the present invention fills the pump with the processing liquid stored in the storage section via the first pipe provided with the first valve, and the second valve is supplied from the pump to the pump. A processing liquid supply program that pumps a processing liquid to a nozzle through a second pipe provided, discharges the processing liquid from the nozzle, and supplies the processing liquid to a substrate to be processed. The first valve is opened. And the second valve is closed to cause the pump to perform a suction operation for a predetermined stroke, and to fill the pump with the processing liquid from the reservoir by the amount corresponding to the stroke; The first valve is switched from the open state to the closed state while keeping the valve closed so that the pressure of the processing liquid remaining in the flow path between the pump and the second valve matches the desired reference standby pressure. So that the pump is controlled by the pressure feedback method. The second valve is switched from the closed state to the open state while keeping the first valve closed, and the pump performs a predetermined stroke discharge operation, and the processing liquid is discharged from the nozzle toward the substrate. And a third step of discharging only the amount of liquid according to.

  In the present invention, after the processing liquid is discharged from the pump by the discharge operation, the suction operation is performed to refill the pump with the processing liquid, and the pressure on the pump outlet side is made to coincide with the reference standby pressure by the pressure feedback control. In preparation for the next discharge operation. As a result, when the processing liquid discharge operation is started on the next substrate to be processed, it is possible to surely prevent the nozzle from dropping or mixing bubbles, and the pump pressure to a desired discharge pressure with a constant rising characteristic. The processing liquid can be supplied to the substrate at a stable flow rate.

  According to a preferred aspect of the present invention, the pump has a variable volume pump chamber that contains the processing liquid, and a reciprocating member that can move bidirectionally on a predetermined path for changing the volume of the pump chamber. And a drive unit that moves the reciprocating member in accordance with a control signal supplied from the standby pressure control unit. More preferably, the reciprocating member may have a piston that can move linearly in both directions on a straight path. The drive unit may include an electric motor and a transmission mechanism that converts a rotational driving force of the electric motor into a linear driving force of the piston.

  According to a preferred aspect, the standby pressure control unit measures the pressure of the processing liquid in the second pipe between the pump and the second valve, and the first pressure measuring unit. A first comparison unit that compares the pressure of the processing liquid measured by the pressure measurement unit with a reference standby pressure to obtain a comparison error, and a first control signal that generates a control signal to be given to the drive unit based on the comparison error And a generation unit. In this case, the standby pressure control unit compares the comparison error obtained from the first comparison unit with a predetermined threshold value, and stops the pressure feedback control for the pump when the comparison error becomes smaller than the threshold value. It's okay.

  According to a preferred aspect, the first pressure measurement unit measures the pressure of the treatment liquid as a relative pressure with respect to the atmospheric pressure. Further, the reference standby pressure is set to a value substantially equal to the atmospheric pressure.

  Alternatively, according to another preferred aspect, the pressure of the processing liquid that remains in the nozzle or in the flow path between the second valve and the nozzle outlet is used as the reference standby pressure. In this case, the standby pressure control unit further includes a second pressure measurement unit that measures the pressure of the processing liquid in the nozzle or in the second pipe between the second valve and the nozzle as the reference standby pressure. Good.

  According to a preferred aspect of the present invention, in order to apply the treatment liquid onto the substrate, the second valve is switched from the closed state to the open state, and the pump is moved forward by a predetermined stroke. In this case, when the processing liquid is pumped from the pump toward the nozzle, a discharge pressure control unit that controls the pump by a pressure feedback method may be provided so that the pressure of the pump follows a preset reference discharge pressure.

  According to a preferred aspect, the discharge pressure control unit compares the pressure of the processing liquid measured by the first pressure measurement unit with the reference discharge pressure to obtain a comparison error; And a second control signal generation unit that generates a control signal to be supplied to the pump based on the comparison error.

  According to a preferred aspect of the present invention, the second valve is switched from the open state to the closed state in order to refill the pump with the treatment liquid after applying the treatment liquid on the substrate, and the first The valve is switched from the closed state to the open state, and the pump is moved back by the predetermined stroke.

  According to a preferred aspect of the present invention, when applying the processing liquid onto the substrate, the scanning unit moves the nozzle relative to the substrate in a predetermined direction in conjunction with the forward movement of the pump. Is provided. The scanning unit preferably starts the relative movement of the nozzle after a predetermined time from the start of the discharge of the processing liquid, and adjusts the relative movement speed of the nozzle in accordance with the timing when the pump pressure rises and reaches a stable value. You can start up to the set speed.

  According to the processing apparatus, the processing liquid supply method, or the processing liquid supply program of the present invention, the reproducibility of the pressure at which the processing liquid is discharged from the nozzle (particularly the pressure at the start of discharge) is obtained because of the above-described configuration and operation. Can improve the processing quality.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a coating and developing processing system as one configuration example to which the processing apparatus, the processing liquid supply method and the processing liquid supply program of the present invention can be applied. This coating / development processing system 10 is installed in a clean room. For example, an LCD substrate is a substrate to be processed, and a series of processes such as cleaning, resist coating, pre-baking, developing, and post-baking in a photolithography process are performed in the LCD manufacturing process. Is what you do. The exposure process is performed by an external exposure apparatus 12 installed adjacent to the processing system.

  In this coating and developing system 10, a horizontally long process station (P / S) 16 is arranged in the center, and a cassette station (C / S) 14 and an interface station (I / F) are arranged at both ends in the longitudinal direction (X direction). ) 18.

  The cassette station (C / S) 14 is a cassette loading / unloading port of the system 10, and up to four cassettes C can be accommodated in a horizontal direction, for example, in the Y direction by stacking square glass substrates G in multiple stages. A cassette stage 20 that can be placed side by side and a transport mechanism 22 that puts and removes the substrate G to and from the cassette C on the stage 20 are provided. The transport mechanism 22 has a means for holding the substrate G, for example, a transport arm 22a, and can be operated with four axes of X, Y, Z, and θ, and the adjacent process station (P / S) 16 side and the substrate G Delivery is now possible.

  In the process station (P / S) 16, the processing units are arranged in the order of the process flow or process on a pair of parallel and opposite lines A and B extending in the system longitudinal direction (X direction). More specifically, the upstream process line A from the cassette station (C / S) 14 side to the interface station (I / F) 18 side includes a cleaning process unit 24, a first thermal processing unit 26, and The coating process section 28 and the second thermal processing section 30 are arranged in a horizontal row. On the other hand, in the downstream process line B from the interface station (I / F) 18 side to the cassette station (C / S) 14 side, a second thermal processing unit 30, a development processing unit 32, and a decolorization process are provided. The unit 34 and the third thermal processing unit 36 are arranged in a horizontal row. In this line configuration, the second thermal processing unit 30 is located at the end of the upstream process line A and at the beginning of the downstream process line B, and straddles between both lines A and B. ing.

  An auxiliary transfer space 38 is provided between the process lines A and B, and a shuttle 40 that can horizontally place the substrate G in units of one sheet is bidirectional in the line direction (X direction) by a drive mechanism (not shown). Can be moved to.

  In the upstream process line A, the cleaning process unit 24 includes a scrubber cleaning unit (SCR) 42, and an excimer is disposed at a location adjacent to the cassette station (C / S) 10 in the scrubber cleaning unit (SCR) 42. A UV irradiation unit (e-UV) 41 is arranged. The cleaning unit in the scrubber cleaning unit (SCR) 42 performs brushing cleaning and blow cleaning on the upper surface (surface to be processed) of the substrate G while transporting the substrate G in the horizontal direction A by roller transport or belt transport. It has become.

  The first thermal processing unit 26 adjacent to the downstream side of the cleaning process unit 24 is provided with a vertical transfer mechanism 46 in the center along the process line A, and a plurality of single-wafer oven units are provided on both front and rear sides thereof. A multi-stage unit section or oven towers (TB) 44 and 48 are provided which are stacked in multiple stages together with a substrate transfer pass unit.

For example, as shown in FIG. 2, an upstream oven tower (TB) 44 includes a substrate carrying pass unit (PASS _L ) 50, dehydrating baking heating units (DHP) 52 and 54, and an adhesion unit. (AD) 56 are stacked in order from the bottom. Here, the pass unit (PASS _L ) 50 provides a space for carrying the substrate G after the cleaning process from the scrubber cleaning unit (SCR) 42 into the first thermal processing unit 26. The oven tower (TB) 48 on the downstream side includes a pass unit (PASS _R ) 60 for carrying out the substrate, cooling units (CL) 62 and 64 for adjusting the substrate temperature, and an adhesion unit (AD) 66 in order from the bottom. Stacked. Here, pass unit (PASS _R) 60 provides a space for unloading the substrate G having undergone the required heat treatment at a first thermal processing unit 26 to the downstream side of the coating process portion 28.

  In FIG. 2, the transport mechanism 46 includes a lift transport body 70 that can be moved up and down along a guide rail 68 that extends in the vertical direction, and a swivel transport body 72 that can rotate or turn in the θ direction on the lift transport body 70. And a transport arm or tweezers 74 that can move back and forth or extend and retract in the front-rear direction while supporting the substrate G on the revolving transport body 72. A drive unit 76 for driving the lifting and lowering conveyance body 70 up and down is provided on the base end side of the vertical guide rail 68, and a driving unit 78 for driving the swiveling conveyance body 72 to rotate is attached to the lifting and lowering conveyance body 70. A drive unit 80 for advancing and retracting 74 is attached to the rotary transport body 72. Each drive part 76,78,80 may be comprised by the electric motor etc., for example.

  The transport mechanism 46 configured as described above can access any unit in the oven towers (TB) 44 and 48 adjacent to each other by moving up and down at high speed, and the shuttle 40 on the auxiliary transport space 38 side. In both cases, the substrate G can be delivered.

  The coating process unit 28 adjacent to the downstream side of the first thermal processing unit 26 includes a resist coating unit (CT) 82 and a vacuum drying unit (VD) 84 along the process line A as shown in FIG. Arranged in a row. The configuration in the coating process unit 28 will be described in detail later.

  The second thermal processing unit 30 adjacent to the downstream side of the coating process unit 28 has the same configuration as that of the first thermal processing unit 26, and a vertical type between the process lines A and B. The transfer mechanism 90 is provided, one oven tower (TB) 88 is provided on the process line A side (last), and the other oven tower (TB) 92 is provided on the process line B side (lead).

Although not shown, for example, in the oven tower (TB) 88 on the process line A side, a substrate loading pass unit (PASS _L ) is disposed at the bottom, and a pre-baking heating unit (PREBAKE) is disposed thereon. For example, they may be stacked in three stages. Further, in the oven tower (TB) 92 on the process line B side, a pass unit (PASS _R ) for carrying out the substrate is disposed at the lowest stage, and a cooling unit (COL) for adjusting the substrate temperature is provided thereon, for example, one stage. The heating unit (PREBAKE) for pre-baking may be stacked thereon, for example, in a two-stage stack.

The transport mechanism 90 in the second thermal processing unit 30 includes the coating process unit 28 and the development process unit 32 via the pass units (PASS _L ) and (PASS _R ) of both oven towers (TB) 88 and 92. Not only can the substrates G be transferred in units of one sheet, but also the substrates G can be transferred in units of sheets to the shuttle 40 in the auxiliary transport space 38 and the interface station (I / F) 18 described later.

  In the downstream process line B, the development process unit 32 includes a so-called flat-flow development unit (DEV) 94 that performs a series of development processing steps while transporting the substrate G in a horizontal posture.

  A third thermal processing unit 36 is disposed downstream of the development process unit 32 with the decolorization process unit 34 interposed therebetween. The decoloring process unit 34 includes an i-ray UV irradiation unit (i-UV) 96 for performing a decoloring process by irradiating the surface to be processed of the substrate G with i-line (wavelength 365 nm).

  The third thermal processing unit 36 has the same configuration as that of the first thermal processing unit 26 and the second thermal processing unit 30, and the vertical transport mechanism 100 along the process line B. A pair of oven towers (TB) 98 and 102 are provided on both the front and rear sides.

Although not shown, for example, in the upstream oven tower (TB) 98, a pass unit (PASS _L ) for carrying a substrate is placed at the lowest stage, and a heating unit (POBAKE) for post-baking is placed thereon, for example. May be stacked in three stacks. Further, in the oven tower (TB) 102 on the downstream side, a post baking unit (POBAKE) is placed at the lowermost stage, and a pass cooling unit (PASS _R · COL) for carrying out and cooling the substrate is placed on the post baking unit (POSBAKE). The heating unit (POBAKE) for post-baking may be stacked in two layers.

The transport mechanism 100 in the third thermal processing unit 36 irradiates with i-line UV via the pass units (PASS _L ) and pass cooling units (PASS _R · COL) of both multi-stage unit parts (TB) 98 and 102. Not only can the unit (i-UV) 96 and cassette station (C / S) 14 and the substrate G be transferred in units of one sheet, but also the substrate G can be transferred in units of one unit to the shuttle 40 in the auxiliary transport space 38. ing.

  The interface station (I / F) 18 includes a transfer device 104 for exchanging the substrate G with the adjacent exposure device 12, and a buffer stage (BUF) 106 and an extension / cooling stage (EXT / COL) around the transfer device 104. ) 108 and peripheral device 110 are arranged. A stationary buffer cassette (not shown) is placed on the buffer stage (BUF) 106. The extension / cooling stage (EXT / COL) 108 is a stage for transferring a substrate having a cooling function, and is used when the substrate G is exchanged with the process station (P / S) 16 side. For example, the peripheral device 110 may have a configuration in which a titler (TITLER) and a peripheral exposure device (EE) are stacked vertically. The transfer device 104 has a means for holding the substrate G, for example, a transfer arm 104a, and transfers the substrate G to and from the adjacent exposure device 12, each unit (BUF) 106, (EXT / COL) 108, (TITLER / EE) 110. Can be done.

FIG. 3 shows a processing procedure in this coating and developing processing system. First, in the cassette station (C / S) 14, the transport mechanism 22 takes out one substrate G from any of the cassettes C on the stage 20, and the cleaning process unit 24 of the process station (P / S) 16. It is carried into the excimer UV irradiation unit (e-UV) 41 (step S ₁ ).

Excimer UV irradiation unit (e-UV) substrate G in the 41 is subjected to dry cleaning by UV irradiation (step S _2). This UV cleaning mainly removes organic substances on the substrate surface. After completion of the ultraviolet cleaning, the substrate G is moved to the scrubber cleaning unit (SCR) 42 of the cleaning process unit 24 by the transport mechanism 22 of the cassette station (C / S) 14.

In the scrubber cleaning unit (SCR) 42, as described above, the substrate G is brushed or blown onto the upper surface (surface to be processed) of the substrate G while being transported in a horizontal position in the horizontal direction by roller transport or belt transport. By performing cleaning, particulate dirt is removed from the substrate surface (step S ₃ ). After the cleaning, the substrate G is rinsed while being conveyed in a flat flow, and finally the substrate G is dried using an air knife or the like.

The substrate G that has been cleaned in the scrubber cleaning unit (SCR) 42 is carried into the pass unit (PASS _L ) 50 in the upstream oven tower (TB) 44 of the first thermal processing section 26 in a flat flow. The

In the first thermal processing unit 26, the substrate G is sequentially transferred to a predetermined oven unit in a predetermined sequence by the transport mechanism 46. For example, the substrate G is first transferred from the pass unit (PASS _L ) 50 to one of the heating units (DHP) 52 and 54, where it is subjected to dehydration (step S ₄ ). Next, the substrate G is transferred to one of the cooling units (COL) 62 and 64 where it is cooled to a constant substrate temperature (step S ₅ ). Thereafter, the substrate G is transferred to an adhesion unit (AD) 56 where it is subjected to a hydrophobic treatment (step S ₆ ). After completion of the hydrophobic treatment, the substrate G is cooled to a constant substrate temperature by one of the cooling units (COL) 62 and 64 (step S ₇ ). Finally, the substrate G is transferred to the pass unit (PASS _R ) 60 in the downstream oven tower (TB) 48.

  As described above, in the first thermal processing unit 26, the substrate G is arbitrarily transferred between the upstream multi-stage oven tower (TB) 44 and the downstream oven tower (TB) 48 via the transport mechanism 46. You can come and go. The second and third thermal processing units 30 and 36 perform the same substrate transfer operation.

The substrate G that has undergone a series of thermal or thermal processing as described above in the first thermal processing unit 26 is applied from the pass unit (PASS _R ) 60 in the downstream oven tower (TB) 48 to the coating process unit. It is moved to 28 resist coating units (CT) 82.

In the resist coating unit (CT) 82, the substrate G is coated with a resist solution on the upper surface (surface to be processed) by a spinless method using a long resist nozzle as will be described later. Next, the substrate G is subjected to a drying process by a reduced pressure drying unit (VD) 84 adjacent to the downstream side (step S ₈ ).

The substrate G subjected to the resist coating process as described above is transferred from the reduced pressure drying unit (VD) 84 to the pass unit (PASS _L ) in the upstream oven tower (TB) 88 of the adjacent second thermal processing unit 30. It is brought in.

Within the second thermal processing unit 30, the substrate G is sequentially transferred to a predetermined unit by the transport mechanism 90 in a predetermined sequence. For example, the substrate G is first transferred from the pass unit (PASS _L) to one of the heating units (PREBAKE), where it undergoes a heat treatment of pre-baking (Step S _9). Next, the substrate G is transferred to one of the cooling units (COL), where it is cooled to a constant substrate temperature (step S ₁₀ ). Thereafter, the substrate G passes through the pass unit (PASS _R ) on the downstream oven tower (TB) 92 side or without the extension cooling stage (EXT COL) on the interface station (I / F) 18 side. ) 108.

In the interface station (I / F) 18, the substrate G is transferred from the extension / cooling stage (EXT / COL) 108 to the peripheral exposure device (EE) of the peripheral device 110, where the resist adhering to the peripheral portion of the substrate G is removed. After receiving an exposure for removal during development, the image is sent to the adjacent exposure apparatus 12 (step S ₁₁ ).

In the exposure device 12, a predetermined circuit pattern is exposed to the resist on the substrate G. When the substrate G that has undergone pattern exposure is returned from the exposure apparatus 12 to the interface station (I / F) 18 (step S ₁₁ ), it is first carried into a titler (TITLER) of the peripheral device 110, where it is placed on the substrate. Predetermined information is written in a predetermined part (step S ₁₂ ). Thereafter, the substrate G is returned to the extension / cooling stage (EXT / COL) 108. Transfer of the substrate G in the interface station (I / F) 18 and exchange of the substrate G with the exposure apparatus 12 is performed by the transfer device 104.

In the process station (P / S) 16, the transport mechanism 90 receives the exposed substrate G from the extension / cooling stage (EXT / COL) 108 in the second thermal processing unit 30, and the oven tower ( TB) is transferred to the developing process section 32 via the pass unit (PASS _R ) in the 92.

In the development process unit 32, the substrate G received from the pass unit (PASS _R ) in the oven tower (TB) 92 is carried into the development unit (DEV) 94. Substrate G in the developing unit (DEV) 94 is conveyed by the flat flow manner toward the downstream process line B, developing during the transport, rinse, a series of development processing step drying is performed (step S _13).

The substrate G subjected to the development process in the development process unit 32 is carried into the decolorization process unit 34 adjacent to the downstream side in a flat flow, where it is subjected to a decolorization process by i-line irradiation (step S ₁₄ ). The substrate G that has been subjected to the decoloring process is carried into the pass unit (PASS _L ) in the upstream oven tower (TB) 98 of the third thermal processing unit 36.

In the third thermal processing unit 36, the substrate G is transferred to the first one of the heating units (POBAKE) from the pass unit (PASS _L), where it undergoes a heat treatment of the post-baking (Step S _15). Next, the substrate G is transferred to a path cooling unit (PASS _R · COL) in the downstream oven tower (TB) 102, where it is cooled to a predetermined substrate temperature (step S ₁₆ ). The transport mechanism 100 transports the substrate G in the third thermal processing unit 36.

On the cassette station (C / S) 14 side, the transport mechanism 22 receives the substrate G that has completed all the steps of the coating and developing process from the pass cooling unit (PASS _R COL) of the third thermal processing unit 36, The received substrate G is accommodated in one of the cassettes C on the stage 20 (step S ₁ ).

  In this coating and developing treatment system 10, the present invention can be applied to the resist coating unit (CT) 82 of the coating process unit 28. Hereinafter, an embodiment in which the present invention is applied to a resist coating unit (CT) 82 will be described with reference to FIGS.

As shown in FIG. 4, the coating process unit 28 arranges a resist coating unit (CT) 82 and a vacuum drying unit (VD) 84 on the support table 112 in a line in the X direction (along the process line A). is doing. A pair of guide rails 114, 114 extending in the X direction are laid in parallel on both ends of the support base 112, and a pair or a plurality of pairs of transfer arms 116, 116 guided and moved by the guide rails 114, 114 move the resist. The substrate G can be transferred from the coating unit (CT) 82 to the vacuum drying unit (VD) 84. Further, the substrate G before coating processing is carried into the resist coating unit (CT) 82 from the pass unit (PASS _R ) of the adjacent oven tower (TB) 48 by the transfer arms 116, 116, and the reduced pressure drying unit (VD) 84. To the pass unit (PASS _L ) of the adjacent oven tower (TB) 88.

  The resist coating unit (CT) 82 includes a stage 118 for horizontally placing and holding the substrate G, and a long resist on the upper surface (surface to be processed) of the substrate G placed on the stage 118. A coating processing unit 122 for applying a resist solution by a spinless method using the nozzle 120, a nozzle refreshing unit 124 for recovering the resist solution discharging function of the resist nozzle 120 while the coating process is not performed, and the like, etc. Have The configuration and operation of each part in the resist coating unit (CT) 82 will be described in detail later with reference to FIGS.

  The vacuum drying unit (VD) 84 includes a tray or shallow container type lower chamber 126 having an open upper surface, and a lid-shaped upper chamber configured to be tightly fitted or fitted to the upper surface of the lower chamber 126. (Not shown). The lower chamber 126 has a substantially quadrangular shape, a stage 128 for horizontally placing and supporting the substrate G is disposed at the center, and exhaust ports 130 are provided at the four corners of the bottom surface. Each exhaust port 130 communicates with a vacuum pump (not shown) via an exhaust pipe (not shown). With the lower chamber 126 covered with the upper chamber, the sealed processing space in both chambers can be depressurized to a predetermined degree of vacuum by the vacuum pump.

  FIG. 5 shows a configuration of the coating processing unit 122 in the resist coating unit (CT) 82. The coating processing unit 122 includes a resist solution supply mechanism 132 including a resist nozzle 120 and a nozzle moving mechanism 134 that horizontally moves the resist nozzle 120 above the stage 118 in the X direction during the coating process. In the resist solution supply mechanism 132, the resist nozzle 120 is a long nozzle extending in the Y direction with a length capable of covering the substrate G on the stage 118 from one end to the other end, and a resist pump 150 (FIG. 6) described later. Connected to a discharge pipe 136 drawn from the pipe. The nozzle moving mechanism 134 includes an inverted U-shaped or gate-shaped support 138 that horizontally supports the resist nozzle 120, and a rectilinear drive unit 140 that linearly moves the support 138 in both directions in the X direction. This linear drive part 140 may be comprised by the linear motor mechanism with a guide, or a ball screw mechanism, for example. In addition, an elevating mechanism 135 with a guide for changing or adjusting the height position of the resist nozzle 120 is provided at, for example, a joint portion 142 that connects the support 138 and the resist nozzle 120. The elevating mechanism 135 adjusts the height position of the resist nozzle 120, whereby the distance interval between the lower end of the resist nozzle 120 or the discharge port 120a and the upper surface (surface to be processed) of the substrate G on the stage 118, that is, the size of the gap. Can be set or adjusted arbitrarily.

  In this embodiment, a pair of joint portions 142L and 142R are connected to both ends of the resist nozzle 120, and the height adjustment of the resist nozzle 120 can be controlled independently at both the left and right ends. Here, with reference to the traveling direction during the coating process, the joint portion 142L connected to the left end portion of the resist nozzle 120 is defined as the left joint portion, and the joint portion connected to the opposite side (the right end portion of the resist nozzle 120). Let 142R be the right joint. The elevating mechanism 135 includes a left Z-axis mechanism 135L on the left joint portion 142L side and a right Z-axis mechanism 135R on the right joint portion 142R side. Both the left and right Z-axis mechanisms 135L and 135R have independent guide portions and drive portions, respectively.

  The resist nozzle 120 is made of a metal excellent in rust resistance and workability, such as stainless steel, and has tapered surfaces 120b and 120c (FIG. 19) that taper toward the discharge port 120a at the lower end. Here, one tapered surface 120b is a front surface facing forward in the traveling direction during the coating treatment, and the other tapered surface 120c is a rear surface facing backward in the traveling direction during the coating processing. The discharge ports 120a may be a slit type extending in the nozzle longitudinal direction, or may be a porous type in which fine diameter discharge holes are arranged at a constant pitch in the nozzle longitudinal direction.

  FIG. 6 shows the overall configuration of the resist solution supply mechanism 132. The resist solution supply mechanism 132 pre-fills the pump 150 with at least one application process (one substrate) of the resist solution R from the bottle 146 that stores the resist solution R via the suction pipe 148. Sometimes, the resist solution is pumped from the pump 150 to the resist nozzle 134 through the discharge pipe 136 at a predetermined pressure, and the resist solution R is discharged onto the substrate G from the resist nozzle 136 at a predetermined flow rate.

The bottle 146 is hermetically sealed, and a pumped gas such as N ₂ gas is supplied from the gas pipe 144 toward the liquid level in the bottle at a constant pressure (for example, 3 kPa with a gauge pressure based on the atmospheric pressure). ing. The gas pipe 144 is provided with an on-off valve 152 made of, for example, an air operated valve.

  A filter 154, a deaeration module 156, and an on-off valve 158 are provided in the middle of the suction pipe 148. The filter 154 removes foreign matter (dust) in the resist solution R sent from the bottle 146, and the degassing module 156 removes bubbles in the resist solution. The on-off valve 158 is composed of, for example, an air operated valve, and is configured to turn on (fully open) or turn off (shut off) the flow of the resist solution R in the suction pipe 148 under the control of the controller 160.

  The pump 150 is preferably a piston pump, and has a pump body 150a having a pump chamber, a piston 150b for arbitrarily changing the volume of the pump chamber, and a pump drive unit 150c for reciprocating the piston 150b. is doing. Here, the pump drive unit 150c has an electric motor for feedback control, such as a servo motor, as a power source, performs piston drive for suction / discharge operation under the control of the controller 160, and adjusts the residual pressure or waits. Piston drive for pressure control can also be performed.

  In the middle of the discharge pipe 136, only the open / close valve 162 is provided as a fluid device, and no filter, suck back valve, or the like is provided. The on-off valve 162 is composed of, for example, an air operated valve, and is configured to turn on (fully open) or turn off (shut off) the flow of the resist solution R in the discharge pipe 136 under the control of the controller 160.

  A pressure sensor 164 is attached to the discharge pipe 136 at an appropriate position between the pump 150 and the on-off valve 162. The pressure sensor 164 is a gauge pressure gauge, measures the pressure of the resist solution R in the discharge pipe 136 at the sensor mounting position with reference to the atmospheric pressure, and outputs an electrical signal (pressure detection signal) representing the measured pressure as the gauge pressure. To do. This pressure detection signal is given to the control unit 160.

  The controller 160 is composed of a microcomputer, for example, loads and executes a resist solution supply program and other programs stored in a storage medium such as an optical disk into the main memory, and applies resist according to a programmed sequence and various set values. Each unit in the unit (CT) 82, in particular, the on-off valves 152, 158, 162 of the resist solution supply mechanism 132, the pump 150, the nozzle moving mechanism 134, the lifting mechanism 135, and the like are controlled.

  7 and 8 show a configuration example of the pump 150 in the resist solution supply mechanism 132. FIG. In the pump 150, a pump chamber for storing or filling the resist solution R is configured by a flexible tube diaphragm 166 having a variable volume, and a pressure medium chamber 172 that surrounds the tube diaphragm 166 in the pump body 150 a is connected via a fixed pipe 170. The bellows 168 is connected, and the bellows 168 is expanded and contracted by the piston 150b. The tube diaphragm 166 has one end (inlet) connected to the suction pipe 148 and the other end (outlet) connected to the discharge pipe 136.

  The bellows 168, the fixed pipe 170, and the pressure medium chamber 172 communicate with each other, and a certain amount of pressure medium such as silicon oil S is sealed therein. The pump drive unit 150c includes a servo motor 174 that generates rotational torque, and a transmission device 176 that converts the rotational drive force of the servo motor 174 into the straight drive force of the piston 150b. The transmission device 176 may be constituted by, for example, a ball screw mechanism or a straight guide portion. The tip of the piston 150b is coupled to one end (movable end) of the bellows 168. The other end (fixed end) of the bellows 168 is coupled to the fixed pipe 170.

For example, when the servo motor 174 rotates in the forward direction to move the piston 150b forward or forward, the movable end of the bellows 168 moves in a direction approaching the fixed end, the bellows 168 contracts, and the silicon oil S is fixed from the bellows 168. The pressure applied to the tube frame 166 increases as the pressure medium chamber 172 is fed through the pipe 170. At this time, if the opening / closing valve 158 of the suction pipe 148 is closed and the opening / closing valve 162 of the discharge pipe 136 is opened, the tube frame 166 contracts and discharges the resist solution R to the discharge pipe 136 side. The discharge pressure is proportional to the movement (forward movement) speed of the piston 150b, and the discharge amount is proportional to the forward movement distance (forward movement stroke) of the piston 150b. In the discharge operation of the coating process, the tip of the piston 150b (movable end of the bellows 168) moves forward from the position (H _a ) in FIG. 7 by a set stroke L to the position (H _b ) in FIG.

When the servo motor 174 rotates in the reverse direction to move the piston 150b backward or backward, the movable end of the bellows 168 moves away from the fixed end, the bellows 168 extends, and the silicon oil S is extracted from the pressure medium chamber 172. The pressure applied to the tube frame 166 is reduced by being sucked into the bellows 168 through the fixed pipe 170. At this time, when the opening / closing valve 158 of the suction pipe 148 is opened and the opening / closing valve 162 of the discharge pipe 136 is closed, the tube frame 166 expands and sucks the resist solution R from the tank 146 side. The suction pressure is proportional to the moving (return) speed of the piston 150b, and the suction amount is proportional to the return distance (return stroke) of the piston 150b. For inhalation or filling operation after the coating process, the tip of the piston 150b is adapted to backward by the set stroke L position to the position of FIG. 7 (H _b) (H _a) in FIG. 8.

  The servo motor 174 of the pump drive unit 150 c rotates by a control signal from the controller 160. In this embodiment, the servo motor 174 or the transmission device 176 is provided with an encoder 178 for detecting the rotation amount (rotation speed) of the servo motor 174 or the movement distance (movement speed) of the piston 150b. Sometimes, a movement distance / speed feedback loop is formed between the encoder 178, the controller 160, and the servo motor 174. Further, as described above, the pressure sensor 164 for detecting the pressure in the discharge pipe 136 is provided between the pump 150 and the on-off valve 162. When adjusting the residual pressure after the suction operation, the pressure sensor 164, the controller 160, and the pump A pressure feedback loop is formed with 150 (pump drive unit 150c, piston 150b, pump body 150a).

  FIG. 9 shows a configuration of a feedback control system for the pump 150 of the controller 160 in this embodiment.

  The moving distance / moving speed feedback loop includes a speed setting unit 180, a stroke setting unit 182, a differentiation circuit 184, comparators 186 and 188, and a suction / discharge control signal generation unit 190. Here, the speed setting unit 180 sets the moving speed of the piston 150b or the rotational speed of the servo motor 174 in the suction / discharge operation, and gives the speed set value to the comparator 186 as a speed command value. The stroke setting unit 182 sets the moving distance (stroke) of the piston 150b or the rotation amount of the servo motor 174 in the suction / discharge operation, and gives the stroke setting value to the comparator 188 as a position command value. The differentiation circuit 184 differentiates the output signal of the encoder 178 attached to the pump 150 to generate a speed detection signal representing the piston moving speed (motor rotational speed).

  The comparator 186 compares the movement speed detection signal from the differentiation circuit 184 with the speed command value from the speed setting unit 180 to obtain a speed error or deviation. The comparator 188 compares the movement distance (rotation amount) detection signal from the encoder 178 with the position command value from the stroke setting unit 182 to obtain a position error or deviation. The suction / discharge control signal generation unit 190 generates a control signal for the servo motor 174 of the pump 150 according to the error value given from the comparators 186 and 188.

The pressure feedback loop includes a pressure setting unit 192, a comparator 194, and a standby pressure control signal generation unit 196. The pressure setting unit 192 sets a residual pressure for adjusting the residual pressure or a reference standby pressure, and supplies the pressure set value P _s to the comparator 194 as a pressure command value. The comparator 194, the pressure detection signal P _x from the pressure sensor 164 as compared to the pressure set value P _s, obtaining a comparison error or differential pressure [Delta] P. The standby pressure control signal generation unit 196 generates a control signal for the servo motor 174 of the pump 150 according to the differential pressure value ΔP given from the comparator 194. In general, the reference standby pressure or the pressure set value P _s may be set to a value equal to the external pressure of the discharge port 120a of the nozzle 120, that is, the atmospheric pressure (0 kPa in gauge pressure).

  The sequence control unit 198 controls each part or the entire operation in the resist coating unit (CT) 82 in a sequence plane, and is a moving distance / moving speed for the pump / feedback control system in the resist solution supply mechanism 132. The feedback loop and the pressure feedback loop are selectively switched at a predetermined timing to operate. The threshold setting unit 200 and the determination unit 202 are for determining the timing for stopping the operation of the pressure feedback loop when adjusting the residual pressure. The determination unit 202 compares the differential pressure value ΔP obtained from the pressure comparator 194 with the set value or threshold value A from the threshold value setting unit 200, and when ΔP ≦ A, a predetermined determination signal or mode An end signal is output to the sequence control unit 198. The determining unit 202 may integrate or average the differential pressure value ΔP and compare it with the threshold value A.

  FIG. 10 to FIG. 13 are flowcharts showing a main operation procedure (control procedure of the controller 160) of the resist solution supply mechanism 132 for the substrate G in the resist coating unit (CT) 82. FIG. 10 shows the procedure of the entire operation, and FIGS. 11, 12, and 13 show the detailed procedure of each operation (steps A2, A3, A4) of FIG. FIG. 14 is a waveform diagram showing temporal characteristics of each part.

When the substrate G is loaded into the unit (CT) 82 and placed on the stage 118 (step A1), the controller 160 causes the nozzle moving mechanism 134 to attach the nozzle 120 to the application start position, and then supplies the resist solution. In the mechanism 132, a resist discharge (application) operation is executed (step A2). In the resist solution supply mechanism 132, the pump 150 is in the state shown in FIG. 7 immediately before starting the resist discharge operation. That is, the piston 150b is located in backward position or standby position L _a, the pump chamber or tubephragm 166 of the pump body 150a is in a state of the resist solution R by a predetermined amount filled. In addition, both the on-off valve 158 for suction and the on-off valve 162 for discharge are closed.

In the resist discharge operation (step A2), the controller 160 switches the discharge on-off valve 162 from the closed state to the open state prior to the start of operation of the pump 150, as shown in FIGS. (Step B1). In this embodiment, the internal pressure of the pump is maintained at a pressure equal to the reference standby pressure P _s, that is, atmospheric pressure (0 kPa) by residual pressure adjustment (step A4), which will be described later. The resist solution R remains almost stationary and does not move (flow) between the nozzle 120 and the discharge port 120a, that is, in the discharge pipe 136. As a result, the resist solution R does not spout from the discharge port 120a of the nozzle 120, and the resist solution R does not retract into the back of the discharge port 120a of the nozzle 120 and bubbles do not enter the resist solution R.

Thus, after the on-off valve 162 is opened and a predetermined time Δt ₁ has passed, the pump 150 starts the forward movement of the piston 150b for discharge (step B2). In this piston forward movement, the above-mentioned moving distance / moving speed feedback loop (FIG. 9) operates, and a control signal of, for example, a PID (proportional / time differential / time integration) method is sent from the suction / discharge control signal generator 190. The servo motor 174 of the pump 150 is given.

When the forward movement of the piston 150b starts, the pressure (discharge pressure) of the pump 150 rises, and the pumping of the resist solution R from the pump 150 to the nozzle 120 is started, and the discharge of the resist solution R from the nozzle 120 onto the substrate G starts. Be started. Since the discharge pipe 136 is not provided with a filter, suck-back valve, or the like, and the pump internal pressure at the start of discharge is always constant at a pressure equal to the reference standby pressure P _s as described above, (A ), The pump pressure rises smoothly up to a predetermined discharge pressure with a constant rise characteristic, and the discharge flow rate of the resist solution R rises stably.

On the other hand, the controller 160 causes the nozzle movement mechanism 124 to start moving or scanning the nozzle 120 in combination with the start of the discharge operation in the resist solution supply mechanism 132. Since the discharge flow rate of the resist solution R does not rise immediately after the start of the pump pressure rise, as shown in FIGS. 14A, 14B, and 14E, only the predetermined time Δt ₂ from the start of the forward movement of the piston 150b. It is preferable to start the nozzle scanning with a delay, and it is preferable to make the nozzle moving speed reach the set scanning speed when the pump pressure reaches the set discharge pressure.

  The piston 150b moves forward at a predetermined constant speed by the action of the moving distance / moving speed feedback loop as described above. Thus, the resist solution R is pumped from the pump 150 to the nozzle 120 side at a constant discharge pressure (for example, 5 kPa as a gauge pressure), and the resist solution R is discharged in a band shape from the nozzle 120 that scans and moves at a constant speed. The resist solution R is applied with a predetermined film thickness so that the carpet is laid on the substrate G.

When the forward stroke reaches the set value L, the controller 160 stops the forward motion of the piston 150b (steps B3 and B4), closes the discharge on-off valve 162 (step B5), and performs the resist discharge operation. (Step A2) is terminated. At this point, the pump 150 is in the state shown in FIG. That is, the piston 150b is located at the forward movement position _Hb, and the pump chamber or the tube diaphragm 166 of the pump main body 150a is in a state of discharging the set amount (one substrate) of the resist solution R. In addition, both the on-off valve 158 for suction and the on-off valve 162 for discharge are closed.

Next, the controller 160 executes the resist suction operation (step A3) after a short time (time Δt ₃ ) after the completion of the resist discharge operation (step A2) as described above. In the resist suction operation, as shown in FIGS. 14B and 14D, the piston 150b starts to move back almost simultaneously with the opening of the suction on-off valve 158 (steps C1 and C2). Even in this piston backward movement, the above moving distance / moving speed feedback loop operates, and a PID control signal is given to the servo motor 174 of the pump 150 from the suction / discharge control signal generator 190 (FIG. 9). Accordingly, the piston 150b moves backward at a predetermined constant speed, and the resist solution R is sucked from the tank 146 side at a constant suction pressure (for example, -2 kPa as a gauge pressure). While the resist solution supply mechanism 132 is performing the resist suction operation in this way, the controller 160 causes the nozzle moving mechanism 134 to perform an operation of returning the resist nozzle 120 from the application end position to the vicinity of the application start position or to the nozzle refresh unit 124. May be.

Eventually, when the backward stroke reaches the set value L in the pump 150, the controller 160 stops the backward motion of the piston 150b (steps C3 and C4), closes the suction on-off valve 158 (step C5), and performs resist suction. The operation (step A3) ends. At this point, the pump 150 is in the state shown in FIG. That is, the piston 150b is returned to near its original position H _a, tubephragm 166 of the pump body 150a is in a state of re-filling the resist solution R in a predetermined amount. In addition, both the on-off valve 158 for suction and the on-off valve 162 for discharge are closed. However, it is uncertain whether the pressure on the outlet side of the pump 150 has returned to the reference standby pressure P _s . Rather, the reproducibility is actually low, which is also a problem of the prior art.

In this embodiment, when the controller 160 finishes the resist suction operation (step A3), the controller 160 performs the residual pressure adjustment (step A4) immediately after or shortly after (Δt ₄ ). In this residual pressure adjustment (step A4), the pressure feedback loop (FIG. 9) operates, and the pressure measured by the pressure sensor 164 is fed back to the standby pressure control signal generator 196, for example, I (time integration) method. Is supplied to the servo motor 174 of the pump 150 (steps D1 and D2). Thus, the pressure or internal pressure on the outlet side of the pump 150 converges or matches the reference standby pressure P _s quickly and accurately by the pressure feedback control (steps D3, D4 → D1,...). The controller 160 ends the residual pressure adjustment (step A4) when the error or the differential pressure ΔP becomes equal to or less than the threshold value A. Thereafter, until the coating process for the next substrate G is executed, each part in the resist solution supply mechanism 132 is placed in the hold state, and the internal pressure of the pump 150 is held at the reference standby pressure P _s .

As described above, in this embodiment, the resist solution supply mechanism 132 replenishes or refills the resist solution for the next application processing from the tank 146 to the pump 150 after finishing the coating processing on one substrate. The suction side on-off valve 158 and the discharge side on-off valve 162 are closed, and the pressure on the outlet side or the internal pressure of the pump 150 is set to the reference standby by pressure feedback control. and so as to coincide with the pressure P _s. As a result, when the coating process is started on the next substrate, it is possible to reliably prevent the resist nozzle 120 from dropping and mixing bubbles, and the pump pressure to a predetermined discharge pressure with a constant rising characteristic. Can stand up. As a result, the film thickness control of the resist coating film becomes easy, and the film thickness uniformity and reproducibility are greatly improved.

  In addition, after the residual pressure adjustment (step A4) is completed, a priming process in which a resist solution is undercoated on the lower part of the back surface 120c of the resist nozzle 120 by the nozzle refresh unit 124 during a period until the coating process for the next substrate G is executed. It is also possible to do this. Hereinafter, the priming process in this embodiment will be described.

  FIG. 15 shows a configuration of the priming processing unit 210 provided in the nozzle refresh unit 124. In the priming processing unit 210, a cylindrical or columnar priming roller 212 extending in the Y direction with a length that covers the entire length of the resist nozzle 120 is disposed in the solvent bath 214. In the solvent bath 214, a solvent or a cleaning liquid (for example, thinner) is accommodated at a level that allows the lower part of the priming roller 212 to be immersed. The priming roller 212 is rotationally driven by a rotation mechanism (not shown). In addition, a wiper 216 is provided in contact with the outer peripheral surface of the priming roller 212 at a position above the cleaning liquid in the solvent bath 214.

  A priming process is performed by the priming processing unit 210 in parallel with loading a new substrate G into the resist coating unit (CT) 82 and loading the substrate G on the stage 118. In this priming process, the resist nozzle 120 is brought close to a position where the nozzle discharge port 120a faces the top of the priming roller 212 with a minute gap, and the resist liquid R is discharged to the resist nozzle 120 at the same time. The roller 212 is rotated in a certain direction (counterclockwise in FIG. 15) by the rotation mechanism. Then, as shown in an enlarged view in FIG. 16, the resist solution R that has come out from the discharge port 120 a of the resist nozzle 120 wraps around the nozzle back surface 120 c and is wound around the outer peripheral surface of the priming roller 212. The outer peripheral surface of the priming roller 212 on which the resist solution is wound immediately enters the solvent bath to wash off the resist solution R. Then, the outer peripheral surface of the priming roller 212 that has risen from the solvent bath is wiped off by the wiper 216, and after the clean surface is restored, it passes under the discharge port 120a of the resist nozzle 120 and receives the resist solution there. . The size (distance) of the gap formed between the discharge port of the resist nozzle 120 and the priming roller 212 is formed between the discharge port of the resist nozzle 120 and the substrate G on the stage 118 during the coating process. It may be set to a value (for example, 40 to 150 μm) that is the same as or close to the gap.

In this priming process, as in the case where the coating process is started as described above, the internal pressure of the pump 150 is maintained at the reference standby pressure P _s (the gauge pressure is 0 kPa) by the previous residual pressure adjustment (step A4). Therefore, the resist solution R can be smoothly discharged from the resist nozzle 120 onto the priming roller 212, and the resist solution R can be circulated to the nozzle back surface 120c side with good reproducibility. Thus, even after the priming process is completed, as shown in FIG. 17, the resist film 120 is left at the lower end of the resist nozzle 120, particularly from the discharge port 120a to the taper back surface 120c.

  In FIG. 15, in order to place the substrate G on the stage 118, a plurality of lift pins 218 rise or protrude from the stage 118 on the coating processing unit 122 side, and transfer arms 116 and 116 (FIG. 4). A substrate G is received. Next, the lift pins 218 are lowered or retracted into the stage 118 while holding the substrate G horizontally, whereby the substrate G is transferred to the upper surface of the stage 118. The lift pin 218 is coupled to a lift pin actuator (not shown) such as a cylinder via a horizontal drive plate 220. When the substrate G is placed on the stage 118, the on-off valve 224 is switched on (opened) by the suction fixing unit 222, and the vacuum force from the vacuum source (not shown) passes through the negative pressure channel. It is given to the suction port 226 on the upper surface of the stage. Thereby, the substrate G is fixed on the stage 118 by receiving a vacuum suction force from the suction port 226.

  The resist nozzle 120 that has undergone the priming process as described above is transferred from the priming processing unit 210 into the coating processing unit 122 by the elevating mechanism 135 and the nozzle moving mechanism 134, and is set at one end of the substrate G on the stage 118. Positioned at the application start position. Thus, at the coating start position, a gap of a set distance D is formed between the ejection port 120a of the horizontal registration nozzle 120 and the substrate G on the stage 118, and the other end in the longitudinal direction of the nozzle from the right end. The liquid film RF fills the gap without any gap up to (left end). In this state, the coating process is started.

In this embodiment, the suction operation (step A3) and the residual pressure adjustment (step A4) can be executed again between the end of the priming process and the start of the coating process on the stage 118. As a result, the discharge (coating) operation is started from a state where the internal pressure of the pump 150 is maintained at the reference standby pressure P _s (gauge pressure of 0 kPa), so that the resist solution is discharged from the discharge port of the resist nozzle 120 as shown in FIG. Can smoothly form a belt-like shape, wrap around the lower part of the back surface of the nozzle, and form a convex meniscus extending straight in the longitudinal direction of the nozzle. Even during the coating process, as shown in FIGS. 19 and 20, the top line WL of the meniscus is stabilized in a horizontal straight line. As a result, the possibility of streaky coating unevenness on the resist coating film RM is greatly reduced.

The preferred embodiment has been described above, but various modifications can be made within the scope of the technical idea of the present invention. For example, in the above-described embodiment, the reference standby pressure Ps in the pressure feedback loop for residual pressure adjustment is set to a value equal to the atmospheric pressure. However, during the standby period, that is, before the discharge on-off valve 162 is opened, the pressure of the resist solution in the nozzle is higher than the atmospheric pressure due to the surface tension in the vicinity of the discharge port of the resist nozzle 120. In this case, the reference standby pressure Ps may be set to a value offset higher than the atmospheric pressure. Alternatively, for example, as shown in FIG. 21, a pressure sensor 230 is attached to the resist nozzle 120 (or the discharge pipe 136 between the on-off valve 162 and the resist nozzle 120), and the inside of the nozzle 120 or the nozzle 120 measured by the pressure sensor 230. The pressure of the resist solution in the close pipe 136 can be set to the reference standby pressure P _s .

  Further, in the above-described embodiment, the pump discharge pressure during application is controlled by the forward movement speed of the piston 150b. As another method, it is also possible to make the pump discharge pressure follow the set pressure by using a pressure feedback loop in the suction / discharge operation. In this case, in FIG. 9, the pressure setting unit 192 gives the set pressure for the suction or discharge operation to the comparator 194, and the suction / discharge control signal generation unit 190 (FIG. 9) replaces the speed error from the comparator 186. Thus, a control signal for the pump 150 may be generated in accordance with the pressure error from the comparator 194.

  The configuration of the tube diaphragm type piston pump 150 in the above embodiment is also an example, and a piston pump or a reciprocating pump of any type / configuration can be used. Further, the check valve 158 for suction can be replaced with a check valve. In the above embodiment, the scanning method is such that the nozzle is moved while the substrate or stage is fixed. However, a scanning method that moves the substrate or stage while fixing the nozzle is also possible.

  Although the above-described embodiment relates to a resist coating apparatus in a coating and developing processing system for LCD manufacturing, the present invention can be applied to any processing apparatus or application that supplies a processing liquid onto a substrate to be processed using a nozzle. It is. Therefore, as the processing liquid in the present invention, in addition to the resist liquid, for example, a coating liquid such as an interlayer insulating material, a dielectric material, and a wiring material can be used, and a developing liquid or a rinsing liquid can also be used. The substrate to be processed in the present invention is not limited to an LCD substrate, and other flat panel display substrates, semiconductor wafers, CD substrates, glass substrates, photomasks, printed substrates, and the like are also possible.

It is a top view which shows the structure of the application | coating development processing system which can apply this invention. It is a side view which shows the structure of the thermal process part in the application | coating development processing system of embodiment. It is a flowchart which shows the procedure of the process in the application | coating development processing system of embodiment. It is a top view which shows the whole structure of the coating process part in the coating development processing system of embodiment. It is a perspective view which shows the structure of the coating process part in the resist coating unit of embodiment. It is a block diagram which shows the structure of the resist liquid supply mechanism in the resist coating unit of embodiment. It is a block diagram which shows the structure (1st state) around the pump in the resist liquid supply mechanism of embodiment. It is a block diagram which shows the structure (2nd state) around the pump in the resist liquid supply mechanism of embodiment. It is a block diagram which shows the structure of the feedback control system with respect to the pump of the controller in embodiment. It is a flowchart figure which shows the procedure of the whole operation | movement in the resist liquid supply mechanism of embodiment. It is a flowchart figure which shows the detailed procedure of the resist discharge (application | coating) operation | movement in embodiment. It is a flowchart figure which shows the detailed procedure of the resist inhalation (filling) operation | movement in embodiment. It is a flowchart figure which shows the detailed procedure of the residual pressure adjustment in embodiment. It is a wave form diagram which shows the time characteristic of each part in embodiment. It is a partial cross section side view showing priming processing and substrate loading in an embodiment. It is a figure which expands and shows the principal part of the priming process of FIG. It is sectional drawing which shows the liquid film state formed in the lower end part of a resist nozzle by priming process. It is a schematic front view which shows the state when attaching a resist nozzle to an application | coating start position in embodiment, and starting a coating process. It is a schematic sectional drawing which shows a mode that a resist coating film is formed behind a resist nozzle during application | coating process in embodiment. It is a perspective view which shows a mode that a resist coating film is formed behind a resist nozzle during application | coating process in embodiment. It is a block diagram which shows the structure of the resist liquid supply mechanism by one modification of embodiment.

Explanation of symbols

10 Process Station 28 Application Process Unit 82 Resist Application Unit (CT)
118 Stage 120 Resist Nozzle 122 Coating Processing Unit 124 Nozzle Refresh Unit 132 Resist Liquid Supply Mechanism 134 Nozzle Movement Mechanism 136 Discharge Pipe 146 Tank 148 Suction Pipe 150 Pump 150b Piston 150c Pump Drive Unit 158 Suction Opening / Closing Valve 160 Controller 162 Discharge On-off valve 164, 230 Pressure sensor 174 Servo motor 190 Suction / discharge control signal generator 192 Pressure setting unit 196 Standby pressure control signal generator

Claims (17)

A nozzle for discharging a predetermined processing liquid to the substrate to be processed;
A reservoir for storing the treatment liquid;
A pump for sucking the processing liquid from the reservoir through a first pipe and pumping the processing liquid toward the nozzle through a second pipe;
A first valve provided in the first pipe;
A second valve provided in the second pipe;
The processing liquid that remains in the flow path between the pump and the second valve under a state in which the second valve is closed after the pump has finished sucking the processing liquid from the storage unit A standby pressure control unit that controls the pump by a pressure feedback system so that the pressure of the pump matches a preset reference standby pressure. The pump
A variable-volume pump chamber for storing the treatment liquid;
A reciprocating member movable in both directions on a predetermined path for changing the volume of the pump chamber;
The processing apparatus according to claim 1, further comprising: a drive unit that moves the reciprocating member in accordance with a control signal supplied from the standby pressure control unit. The reciprocating member has a piston that can move linearly in both directions on a straight path,
The processing apparatus according to claim 2, wherein the driving unit includes an electric motor and a transmission mechanism that converts a rotational driving force of the electric motor into a linear driving force of the piston. The standby pressure control unit is
A first pressure measuring unit that measures the pressure of the processing liquid in the second pipe between the pump and the second valve;
A first comparison unit that compares the pressure of the processing liquid measured by the first pressure measurement unit with the reference standby pressure to obtain a comparison error;
The processing apparatus according to claim 1, further comprising: a first control signal generation unit that generates a control signal to be supplied to the drive unit based on the comparison error.   The standby pressure control unit compares the comparison error obtained from the first comparison unit with a predetermined threshold value, and stops feedback control for the pump when the comparison error becomes smaller than the threshold value. The processing apparatus according to claim 4.   The processing apparatus according to claim 4, wherein the first pressure measuring unit measures the pressure of the processing liquid as a relative pressure with respect to an atmospheric pressure.   The processing apparatus according to claim 1, wherein the reference standby pressure is substantially equal to atmospheric pressure.   The process according to any one of claims 1 to 6, wherein the reference standby pressure is substantially equal to a pressure of the processing liquid remaining in a flow path between the second valve and the discharge port of the nozzle. apparatus.   A second pressure measuring unit configured to measure, as the reference standby pressure, the pressure of the processing liquid in the nozzle or in the second pipe between the second valve and the nozzle. The processing apparatus according to claim 8.   10. The device according to claim 1, wherein the second valve is switched from a closed state to an open state in order to apply the processing liquid onto the substrate, and the pump is moved forward by a predetermined stroke. 11. Processing equipment.   11. A discharge pressure control unit that controls the pump by a pressure feedback method so that the pressure of the pump follows a preset reference discharge pressure when the processing liquid is pumped from the pump toward the nozzle. The processing apparatus as described in. The discharge pressure control unit is
A second comparison unit that compares the pressure of the processing liquid measured by the first pressure measurement unit with the reference discharge pressure to obtain a comparison error;
The processing apparatus according to claim 11, further comprising: a second control signal generation unit that generates a control signal to be supplied to the pump based on the comparison error.   After the treatment liquid is applied on the substrate, the second valve is switched from the open state to the closed state and the first valve is opened from the closed state to refill the pump with the treatment liquid. The processing apparatus according to claim 1, wherein the pump is moved backward by the predetermined stroke.   A scanning unit that moves the nozzle relative to the substrate in a predetermined direction in conjunction with the forward movement of the pump when applying the processing liquid onto the substrate. The processing apparatus as described.   The scanning unit starts the relative movement of the nozzle after a predetermined time from the start of the discharge of the processing liquid, and the relative movement speed of the nozzle in accordance with the timing at which the pump pressure rises and reaches a stable value The processing apparatus according to claim 14, wherein the system is started up to a set speed. The processing liquid stored in the storage unit is filled into the pump through the first pipe provided with the first valve, and the pump is supplied from the pump through the second pipe provided with the second valve. A processing liquid supply method for pumping the processing liquid to a nozzle, discharging the processing liquid from the nozzle and supplying the processing liquid to a substrate to be processed,
The first valve is opened and the second valve is closed, causing the pump to perform a suction operation for a predetermined stroke, and the treatment liquid is supplied from the reservoir by the amount corresponding to the stroke. A first step of filling the pump;
While maintaining the second valve in the closed state, the first valve is switched from the open state to the closed state, and the pressure of the processing liquid remaining in the flow path between the pump and the second valve is changed. A second step of controlling the pump in a pressure feedback manner to match a desired reference standby pressure;
The second valve is switched from the closed state to the open state while keeping the first valve closed, and the pump performs a discharge operation of a predetermined stroke, and the processing liquid is directed from the nozzle toward the substrate. And a third step of discharging a liquid amount corresponding to the stroke. The processing liquid stored in the storage unit is filled into the pump through the first pipe provided with the first valve, and the pump is supplied from the pump through the second pipe provided with the second valve. A processing liquid supply program that pumps the processing liquid to a nozzle, discharges the processing liquid from the nozzle, and supplies the processing liquid to a substrate to be processed.
The first valve is opened and the second valve is closed, causing the pump to perform a suction operation for a predetermined stroke, and the treatment liquid is supplied from the reservoir by the amount corresponding to the stroke. A first step of filling the pump;
While maintaining the second valve in the closed state, the first valve is switched from the open state to the closed state, and the pressure of the processing liquid remaining in the flow path between the pump and the second valve is changed. A second step of controlling the pump in a pressure feedback manner to match a desired reference standby pressure;
The second valve is switched from the closed state to the open state while keeping the first valve closed, and the pump performs a discharge operation of a predetermined stroke, and the processing liquid is directed from the nozzle toward the substrate. And a third step of discharging a liquid amount corresponding to the stroke.

Images